package Bite;
import java.util.Scanner;



public class Test {
    public static void main1(String[] args) {
        Scanner in = new Scanner(System.in);
        //1.读入数据
        int n = in.nextInt(), m = in.nextInt(), q = in.nextInt();
        int[][] arr = new int[n + 1][m + 1];
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= m; j++) {
                arr[i][j] = in.nextInt();
            }
        }
        //2.预设一个前缀和数组
        long[][] dp = new long[n + 1][m + 1];
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= m; j++) {
                dp[i][j] = dp[i - 1][j] + dp[i][j - 1] + arr[i][j] - dp[i - 1][j - 1];
            }
        }

        //3.使用前缀和
        while (q > 0) {
            int x1 = in.nextInt(), y1 = in.nextInt(), x2 = in.nextInt(), y2 = in.nextInt();
            System.out.println(dp[x2][y2] - dp[x1 - 1][y2] - dp[x2][y1 - 1] + dp[x1 - 1][y1 - 1]);


            q--;
        }
    }

    public static void main(String[] args) {


        int[] nums = {1, 4 ,5,6,4,2,8,2,9,1};
        int n = nums.length;
        int[] f = new int[n];
        int[] g = new int[n];

        //2.预设一个前缀和数组
        for (int i = 1; i < n; i++) {
            f[i] = f[i - 1] + nums[i - 1];
        }
        for (int i = n - 2; i >= 0; i--) {
            g[i] = g[i + 1] + nums[i + 1];
        }
        //3.使用前缀和数组
        for (int i = 0; i < n; i++) {
            if (f[i] == g[i]) {
               System.out.println(i);
            }else{
                System.out.println(-1);
            }
        }

    }
}